Q&A.

Lily bulbs need well-drained soil

Q. A few of my early-blooming Asiatic lilies were covered with soft brown spots this year. What could cause this?

--Penelope Shorter, Oak Park

A. Soft brown spots or lesions on foliage, stems or flower petals of bulbs usually indicate a fungal condition, perhaps even rot.

Bulbs prefer well-drained soil with even moisture during their active growth. They will rot out if trapped in waterlogged soil, even for short periods of time. The heavy rains this spring saturated some garden soil, promoting bacterial rot, soft rot and fungal decay of roots and bulbs. Dig up the lily bulbs and inspect them carefully for signs of rot--blackened, soft, foul-smelling sections. Discard all damaged bulbs. Try to plant your summer- and spring-blooming bulbs in an elevated area of the garden where drainage is excellent and where they can benefit from a dormant dry period after they flower.

Q. I have a `Miss Kim' lilac that bloomed for two years and then stopped. I bought another one and planted it next to the original. Neither one is blooming. They're beautiful bushes, but I want flowers.

--Rita Rydin, Darien

A. Lilacs require full sun to produce the fragrant blossoms we cherish. Although they can be quite tolerant of infertile soil, two applications of a balanced 10-10-10 fertilizer are helpful: the first in early April and the second right after the blossoms fade (which is usually early to mid-June in the Chicago area).

But no amount of fertilizer will help when the shrubs are planted in shade. If you can, transplant your lilacs very early next spring, before they break bud, to a full-sun site in your garden. Growing lilacs in too much shade results in frustration, poor or no flowering and powdery mildew on the foliage. Pruning lilacs at the wrong time also can result in fewer flowers. Always prune them immediately after they bloom.

A. One of the primary pests of the indoor ficus tree is scale, a sucking insect that feeds on leaf juices and then emits a sticky, clear liquid known as honeydew. Check the leaves, petioles and small twigs of your ficus for small, rounded brown "dots" that scrape off easily with a fingernail. These brown coverings are created by the scale insect as protection.

Advanced infestations are difficult to control and some gardeners discard heavily damaged plants rather than resort to years of spraying. If possible, take the plant outside to a partially shaded area and spray thoroughly with a lightweight oil labeled for houseplant use. Follow label directions carefully. Scale does have natural enemies, including insect-eating birds. If the plant spends the summer outdoors, they might help control the problem too.